The annual ritual of fending off the flu is more complicated than usual this fall as Americans weigh the opportunity to receive two vaccines to protect against different types of influenza.
The vaccine to fight seasonal flu is already widely available to people of all ages and health conditions, although some areas have reported supply delays or shortages. But a new vaccine to protect against the H1N1 virus, commonly known as swine flu, is just starting to make its way to schools, public health departments and doctors' offices.
Because of an initial limited supply, the first doses of swine flu vaccine are earmarked for people at high risk of serious complications from swine flu and those at risk of spreading it to them. States have ordered about 8 million doses so far, with the potential for up to 250 million total doses, depending on demand, according to the Centers for Disease Control and Prevention in Atlanta.
Public health officials say everyone who wants a swine flu vaccine eventually will be able to get one as more come on line.
The first question many people are asking is if they need one or both of the vaccines.
Nearly all Americans, or 88 percent of the population, fall into a group that's recommended to receive the seasonal flu vaccine, said CDC spokesman Tom Skinner. About half the population fits into a category deemed high priority for the swine flu vaccine.
"People who are recommended to get those vaccines need to plan to get both of them," Skinner said.
While some flu cases involve only several days of misery, others go on to become life-threatening or even fatal. Since the swine flu emerged in the U.S. in April, more than 800 people with flu symptoms have died, including 28 pregnant women and 86 children. Most of those children had an underlying condition, but 20 percent to 30 percent of them were otherwise healthy. The seasonal flu sends an average of 200,000 Americans to the hospital and kills 36,000 of them every year.
People who've come down with a flu-like illness recently may think they had swine flu and that they no longer need a vaccine to prevent it.
But there are hundreds of other respiratory viruses circulating with symptoms that often overlap, and people with mild cases of suspected flu aren't sent for laboratory confirmation of the H1N1 virus, making it impossible to know for sure if they've built immunity, said Dr. Greg Poland, director of the Vaccine Research Group at the Mayo Clinic in Rochester, Minn.
"Because there's no harm in getting the vaccine even if you think you had (swine flu), we err on the side of caution and say you should get the vaccine," Poland said.
While vaccination doesn't confer 100 percent protection against the flu, it's still the most effective way to prevent it or mitigate its harm to the body, according to the CDC.
Clinical trials of the H1N1 vaccine showed it has many of the same side effects as the seasonal variety, chiefly a sore arm at the injection site. People with a known allergy to chicken eggs and those with suppressed immune systems should talk to their doctor about whether flu vaccination is an option for them.
The swine flu vaccine is manufactured the same way as its seasonal counterpart, and the H1N1 strain may have been included in this year's seasonal vaccine had the virus emerged a few months earlier when planning for the seasonal vaccine was under way, said Dr. Paul Offit, chief of infectious disease at the Children's Hospital of Philadelphia.
The seasonal flu vaccine has been used for decades in formulations that change every year to reflect the three most dominant strains of virus that scientists believe will be circulating when the vaccine goes into production in the spring.
The swine flu virus makes up the vast majority of flu bugs now going around, and people in high-risk groups are urged to get a swine flu vaccine as soon as they become available. The groups who are first priority are pregnant women, children and young adults age 6 months to 24 years old, people who are around children too young to be immunized, those age 25 to 64 who have underlying chronic medical conditions such as diabetes or asthma, and health care workers.
More people are recommended to be vaccinated against seasonal flu since, unlike swine flu, it tends to hit the elderly hard as well. About 82 million doses of that vaccine have shipped, and manufacturers are expected to produce about 114 million doses total this year.
"The reason to get both is you want to be protected from the strains most likely to circulate," Offit said.
People who want one or both vaccines may have to be patient until more supply arrives, and they're wise to call ahead to see if the vaccines they want are available.
They also should ask about price and insurance coverage. Some employers and health insurers offer discounts or full reimbursement for flu vaccines. Medicare beneficiaries can receive both vaccines free of charge after satisfying their Part B deductible.
The swine flu vaccine is free for anyone who wants it, though health care providers may charge an administration fee. Uninsured and underinsured children may receive free vaccines through the government's Vaccines for Children Program.
There is high demand for seasonal flu vaccine at Walgreens stores around the country, said company spokesman Jim Cohn in Deerfield, Ill. This year Walgreens is offering the seasonal flu vaccine seven days a week either by appointment or on a walk-in basis. The cost without Medicare or private insurance is $24.99 for the shot and $29.99 for the nasal-spray version.
"I would strongly encourage people interested in getting a (seasonal vaccine) to do so as soon as possible because we're hearing about shortages or locations that are just out," Cohn said.
A handful of Walgreens stores also offer the swine flu vaccine.
Influenza is notoriously unpredictable, but problems with flu vaccine distribution are not.
"We now -- and it's not easy -- have the industrial capacity to make a lot of vaccine efficiently and quickly, and that's good," Offit said. "But what we don't have yet is the distribution method to allow for easy, quick and efficient vaccination."
For people who choose to get either or both flu vaccines, the next questions are often what form they should pick -- the shot or the nasal spray -- and how far apart the immunizations should be if they get both the regular and swine flu vaccines.
Only healthy people ages 2 to 49 who aren't pregnant can receive the nasal-spray versions. People who fit that criteria and are looking to avoid needles for both flu vaccines need to wait four weeks between the two nasal-spray versions, said the CDC's Skinner.
Children ages 6 months to 9 years who have never received a flu vaccine before are recommended to receive two doses of both the H1N1 and seasonal flu vaccine about a month apart, Offit said.
People age 10 and older need only one dose of swine flu vaccine, according to the CDC.
(c) 2009, MarketWatch.com Inc.
Visit MarketWatch on the Web at www.marketwatch.com
Distributed by McClatchy-Tribune Information Services.
Explore further: Flu season: How many shots?